Pesticide Poisoning

Includes organophosphates and carbamates

Inhibit the enzyme acetylcholinesterase and increase acetylcholine activity at nicotinic and muscarinic receptors and in the peripheral and central nervous systems

Most are absorbed through intact skin

Most chemical warfare "nerve agents" (such as GA [tabun], GB [sarin], GD [soman] and VX) are organophosphates

Abdominal cramps

Diarrhea

Vomiting

Excessive salivation

Sweating

Seizures

Lacrimation

Constricted pupils

Wheezing

Bronchorrhea

Skeletal muscle fasciculations

Weakness

Respiratory arrest

Initial tachycardia may be followed by bradycardia

Symptoms may persist or recur for days, especially with highly lipid-soluble agents such as fenthion or dimethoate

Serum and red blood cell cholinesterase activity is usually at least 50% below baseline with severe intoxication

Serum or urine levels of specific pesticides rarely available nor helpful

For recent ingestions, consider gut decontamination by aspiration of the liquid using a nasogastric tube followed by administration of activated charcoal

If the agent is on the victim's skin or hair, wash with soap or shampoo and water

Care providers should avoid skin exposure by wearing gloves and waterproof aprons

Dilute hypochlorite solution (eg, household bleach diluted 1:10) is reported to help break down organophosphate pesticides and nerve agents on equipment or clothing

Administer atropine, 2 mg intravenously, and give repeated doses as needed (may need several hundred milligrams) to dry bronchial secretions and decrease wheezing

Administer pralidoxime, 1–2 g intravenously, as soon as possible, and give a continuous infusion (200–500 mg/h) as long as there is any evidence of acetylcholine excess

Pralidoxime is of questionable benefit for carbamate poisoning